In a manufacturing process of a semiconductor device or a flat panel display (FPD), a substrate processing apparatus has been widely used to perform a cleaning process or an etching process by supplying a processing solution onto a semiconductor wafer or a glass substrate as a processing target substrate.
The substrate processing apparatus includes a substrate transfer chamber elongated in a central region of a rectangular box-shaped housing and a plurality of substrate processing chambers arranged on left and right sides along the substrate transfer chamber.
In the substrate processing apparatus, a substrate is transferred into each of the substrate processing chamber by a substrate transfer device installed within the substrate transfer chamber. After various processes are performed on the substrate in the respective substrate processing chambers, the processed substrate is unloaded from the substrate processing chamber by the substrate transfer device.
In such a substrate processing apparatus, in order to maintain clean air atmosphere within the substrate transfer chamber, a fan filter unit and an air exhaust unit are installed at a ceiling and a bottom of the substrate transfer chamber, respectively, as a clean air flowing unit.
In the substrate processing apparatus having such a configuration, clean air is sucked into the substrate transfer chamber by the fan filter unit and then is exhausted by the air exhaust unit. Accordingly, the clean air is flown downward within the substrate transfer chamber from the top (see, for example, Patent Document 1).
Patent Document 1: Japanese Patent Laid-open Publication No. 2008-34490
In the conventional substrate processing apparatus as stated above, however, if the number of the substrate processing chambers arranged on the lateral sides of the substrate transfer chamber is increased so as to improve processing capacity, the clean air flowing unit including the fan filter unit and the air exhaust unit installed within the substrate transfer chamber may be scaled up, resulting in increase of energy consumption or manufacturing cost.
Furthermore, in case that the substrate processing chambers or the substrate transfer chambers are vertically arranged in multiple levels, a configuration of the clean air flowing unit would become complicated, resulting in scale-up of the apparatus or increase of manufacturing cost.